The present disclosure generally relates to imaging systems, and more particularly relates to the acquisition of three-dimensional images (3D images), that is, images where, for each pixel of the image, a value relative to the distance between the photographed scene and the acquisition device is available. The set of values relative to the distance between the photographed scene and the acquisition device defines a depth map of the scene. The present disclosure more particularly relates to a method of constructing a depth map of a scene and to a device capable of implementing this method. The present disclosure also relates to the acquisition of a fully focused image of a scene.